Hempcrete & Healthy Materials in Austin

Henry Valles led Austin's first hempcrete home in 2017. He's the local expert at the intersection of carbon-negative construction and healthy-material residential design.

2017
Austin's First Hempcrete Home
100–165 lbs
CO₂ Sequestered per m³
0 VOC
Off-Gassing in Hempcrete Walls
Carbon-Neg.
Possible Lifecycle Profile
Parsons
Healthy Materials Lab Cert
3
Speaking Venues (SXSW, EarthX, IHBS)

What Hempcrete Is

Hempcrete is a bio-composite of hemp hurd (the woody inner core of the industrial hemp plant), a lime-based binder, and water. It's typically cast in place inside a wood structural frame, or used as pre-fabricated blocks. Hempcrete itself is non-load-bearing — it functions as a high-performance, hygrothermal infill that handles insulation, vapor management, and acoustic performance in a single homogeneous wall.

Why It Matters

Carbon SequestrationThe hemp plant pulls CO₂ from the atmosphere as it grows. Hempcrete walls store that carbon for the life of the building — credible estimates place sequestration at 100–165 lbs of CO₂ per cubic meter of cast hempcrete, accounting for the lime binder's offsetting emissions. A residential wall assembly can be carbon-negative on a lifecycle basis.
Hygrothermal PerformanceHempcrete walls regulate temperature and moisture together. They buffer humidity (reducing mold risk), provide thermal mass, and offer modest insulating value (R≈2 per inch). At a typical 12" wall thickness, the assembly performs well in the Austin climate.
Non-Toxic, RecyclableHempcrete walls do not off-gas VOCs. They are mineral and plant-based, fully compostable / recyclable at end of life, and pose no respiratory hazards during occupancy.
Fire & Pest ResistanceThe lime binder gives hempcrete excellent fire performance and resistance to pests and rot — it does not provide nutrients to mold, termites, or rodents.

Austin's First Hempcrete Home (2017)

In 2017, Henry led the initiative to bring hempcrete to Community First Village — a 51-acre master-planned residential community in East Austin developed by Mobile Loaves & Fishes for individuals exiting chronic homelessness. The hempcrete project at the Village paired carbon-negative, non-toxic, healthy construction with social impact, and remains a reference point for hempcrete construction in Texas.

Henry has since presented this work and the broader case for hempcrete construction at:

Healthy Materials — The Broader Practice

Hempcrete is one expression of a larger practice: specifying construction materials by their toxicity profile, not just their performance specs. The Healthy Materials Lab at Parsons School of Design — where Henry holds a Healthier and Sustainable Building certificate — is the leading academic center on this.

Material categories Henry evaluates

CategoryHealthy-material targets
Paints, sealants, adhesivesLow- or zero-VOC; no formaldehyde, no phthalates
Cabinetry & substratesNAUF (no added urea formaldehyde) plywood and MDF; CARB Phase 2 compliant
FlooringPVC-free; FloorScore certified; no antimicrobial pesticides
InsulationMineral wool, cellulose, hempcrete, sheep's wool — avoiding fiberglass with formaldehyde binders
Plumbing fixturesLead-free certified; PEX-A or copper, avoiding suspect plastics where possible
Air filtrationMERV-13 minimum; HEPA where indicated; tested ERV/HRV ventilation

Certifications worth understanding

How Henry Helps

Frequently Asked Questions

What is hempcrete?

Hempcrete is a bio-composite building material made from the woody inner core of the hemp plant (the hurd or shiv), a lime-based binder, and water. It is used as cast-in-place wall infill or as pre-fabricated blocks. Hempcrete is non-load-bearing and is paired with a structural frame (typically wood) to form a complete wall assembly.

Why is hempcrete a sustainability story?

Three reasons: (1) it sequesters carbon — hempcrete walls actively store CO₂ that the hemp plant pulled from the atmosphere as it grew; (2) it has excellent hygrothermal performance, meaning it manages temperature and moisture together in ways that reduce mold risk and HVAC load; (3) it's non-toxic — no VOCs off-gas from a hempcrete wall, and the material is fully recyclable and compostable at end of life.

How much carbon does hempcrete sequester?

Estimates vary by mix design, but credible studies place hempcrete carbon sequestration around 100–165 lbs of CO₂ per cubic meter of cast wall, accounting for the lime binder's offsetting emissions. A typical residential wall assembly can be carbon-negative on a lifecycle basis — meaning the wall itself stores more CO₂ than was emitted to make and install it.

Is hempcrete legal in Texas?

Yes. Industrial hemp cultivation and use of hemp-derived building materials is legal in Texas under the 2018 federal Farm Bill and Texas's hemp program. The material itself is approved under the IRC alternative-materials provisions, and there are now multiple AEGB- and code-compliant hempcrete homes in Austin and Texas.

Where is the first hempcrete home in Austin?

Henry Valles led the initiative to build Austin's first hempcrete home at Community First Village in 2017 — a community for individuals exiting chronic homelessness. It paired non-toxic, healthy construction with social impact, and remains a reference point for hempcrete construction in Texas.

What is 'healthy materials' in residential construction?

Healthy materials is the practice of selecting building products that minimize toxicity to occupants and workers across the lifecycle: low/no VOCs in paints, sealants, and adhesives; formaldehyde-free cabinetry and substrates; PVC-free flooring; lead-, phthalate-, and antimicrobial-free fixtures; transparent ingredient disclosure (Cradle to Cradle, Declare, Health Product Declarations). The Healthy Materials Lab at Parsons School of Design — where Henry holds a certificate — is the leading academic center on this.

Can I find hempcrete or healthy-material homes for sale in Austin?

Yes — though they are still a small share of the inventory. Henry tracks hempcrete projects, deeply healthy-material custom builds, and developments where this is part of the brief. He can also advise buyers commissioning new construction or retrofitting an existing home with healthy-material principles.

Work with HenryBuilding a hempcrete home, sourcing a healthy-materials new build, or retrofitting an existing house? Henry can help.henry@henryvalles.com